Dell Studio 1558 (Early 2010) - Manual (Page 67)

Navigation Devices (Mouse, Keyboard, Touch Pad)
67
1 full keyboard/touch pad brightness.
2 half keyboard/touch pad brightness.
3 no lighting.
Changing the Input Language of Your Keyboard
Windows Vista
1 Click Start → Control Panel→ Clock, Language, and Region→
Regional and Language Options.
2 Click Change keyboards or other input methods.
3 On the Keyboards and Languages tab, click Change keyboards.
4 Under Installed services, click Add.
5 Click the language you want to add, select the text services you want to
add, and then click OK.
NOTE:
If the Language bar is not visible, right-click the taskbar, point to Toolbars,
and then click Language bar.
6 Click the Input language button on the language bar.
7 Select the input language you want to use.
8 Click the Keyboard layout button, and then select a keyboard layout.
Windows XP
1 Click Start → Control Panel→ Date, Time, Language, and
Regional Options → Regional and Language Options.
2 On the Regional Options tab of the Regional and Language Options
window, select a language and click OK.